Event details subject to change. Please confirm all information via event website.
Runnin’ of the Green Lucky 7K
Feeling the luck o' the Irish? Lace-up and chase the rainbow in Denver’s favorite Irish-themed run! Join us at Washington Park for some shenanigans! Runnin' of the Green (ROTG) is […]
Three Creeks Half Marathon
Racing Underground brings you an amazing half marathon this spring! The Three Creeks Half Marathon features a half marathon course that is flat, fast and scenic! Travel on foot through […]
Mountain Ridge Trail Race
Mountain Ridge takes place near Highlands Ranch primarily on the Douglas County East-West Regional Trail. This gently rolling course will keep the Heart Rate pumping while offering some of the […]
Platte River Half Marathon
Denver's oldest half marathon runs along the Platte River Trail, covering parts of Littleton and Denver.
Rattler Trail Race
Rattler was created to feature one of Colorado Springs' best city parks, Palmer Park. Runners will enjoy views of the city and Pikes Peak from the sandstone bluffs, while running […]
Greenland Trail Race
The Greenland Trail Race offers four outstanding distances in southern Douglas County. Run the 4 Miler, the 8 Miler, the 25K, or tackle the 50K ultramarathon, Colorado’s fastest 50K! With Pikes Peak as your backdrop, you’ll cruise over a soft dirt trail on your way to a new personal best. With chip timing, an innovative technical running shirt in men’s and women’s sizing, food and beer at the finish, this race will make you want to come back for more!
Colorado Marathon
Marathon, Half Marathon, 10k, 5k and 3-Person Marathon Relay. Marathon, Marathon Relay and Half Marathon runners get to run down the scenic, downhill Poudre Canyon to the finish in Old […]
Wine Run 5K
Like Running or Walking? Love Wine? This race is for you! Join us on Saturday, May 8, 2027 at 9:30am and 11:00am (you will pick your start time during registration) […]
North Fork Trail Race
The North Fork 50 Mile/50K is 100% trails, mainly single track and some double track, starting and finishing along lovely Buffalo Creek, in the mountains about 50 miles southwest of […]
Barr Lake Trail Race
The Barr Lake Trail Race returns to Brighton, CO, offering beautiful lake views and a prime opportunity for new PRs. Now in its sixth year, this event features our flattest […]
Colorado Triathlon
The Colorado Triathlon is where Colorado comes to race! The Colorado Triathlon - sprint & olympic distances, duathlon & aquabike options . To make this the "can't miss" event of […]
Lory Off-Road Triathlon
XTERRA Lory Triathlon is the perfect kick-off to the year for the seasoned off-road triathlete, or a great opportunity for the road triathlete wanting to try out a mountain bike […]
Boulder Peak Triathlon
The Boulder Peak Triathlon, Duathlon & Aquabike on July 10th is one of the countries longest and most well-known triathlons. For the veteran or first time racer, this is THE […]
Steamboat Lake Triathlon
After last summer this event instantly became a personal favorite for our staff, volunteers, and athletes - come find out why! We couldn't be more excited about this course, this […]
Backcountry Marathon
Utilizing the beautiful trails that surround Aspen, and now offering three distances - 50K, marathon and heavy half-marathon, all of which run almost exclusively on dirt trails. For the first […]
Stagecoach Gravel Triathlon
We didn't get the chance to launch this race in 2020, but that didn't diminish our passion for this brand new style of triathlon! To say this race is “unique” […]
Westminster Trail Race
Wayne Carle Middle School 10020 100th Ave, Westminster, CO, United StatesAfter a special night edition last year, Westminster returns to its traditional daytime format in 2026 — bringing runners back to a classic morning on the trails at Standley Lake. […]
Outdoor Divas Triathlon
The Outdoor Divas Sprint Triathlon on August 21st, annually awarded best women's event in Colorado by Competitor Magazine, is the all women's triathlon you've been waiting for! We intentionally keep […]
Chase the Moon Trail Race
Chase the Moon is a 12-hour team relay and solo ultramarathon, run overnight under the light of the full moon in the Highlands Ranch Backcountry trail system (we promise some […]
Rock Hawk Trail Race
Held on the gorgeous, thrilling and rolling trails of Castle Rock’s Miller Park & Ridgeline Trail systems. While not overly technical, these trails will challenge and excite, as you soak […]
Snow Mountain Ranch Trail Festival
Join us at the YMCA of the Rockies in Granby for the annual Snow Mountain Ranch Trail Running Festival. This event features 4 races with 2 different "challenges". Races will […]
Littlefoot Sprint Triathlon
Enjoy a fun late season tri at beautiful Bear Creek Lake Park in a land before time. Set at the base of the foothills, the Littlefoot Triathlon starts off with […]
Oktoberfest Triathlon
The annual Oktoberfest Triathlon on Saturday September 24th, 2022, is the party of the season and also a 2022 Mountain Collegiate Conference Race! As the leaves change color this race […]
Bear Chase Trail Race
The Bear Chase Race Endurance Festival is a 100K, 50 Mile, 50K, Half Marathon, Baby Bear 10K and 5K trail race at beautiful Bear Creek Lake Park, in Lakewood, CO. […]
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